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Volcano Hazards Program

Find U.S. Volcano

There are about 170 potentially active volcanoes in the U.S. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption through our National Volcano Early Warning System. We deliver forecasts, warnings, and information about volcano hazards based on a scientific understanding of volcanic behavior.

News

Volcano Watch — Mauna Loa has lessons to teach during quiet times

Volcano Watch — Mauna Loa has lessons to teach during quiet times

Photo & Video Chronology — February 16, 2026 — Kīlauea episode 42 fountains and fallout

Photo & Video Chronology — February 16, 2026 — Kīlauea episode 42 fountains and fallout

Volcano Watch — New Hawaii citizen science tool: Is Tephra Falling?

Volcano Watch — New Hawaii citizen science tool: Is Tephra Falling?

Publications

Forecasting volcanic activity in Germany—A multi-criteria approach Forecasting volcanic activity in Germany—A multi-criteria approach

Igneous activity, including shallow intrusions and volcanism, has the potential to disrupt underground critical infrastructure. Notably, future underground infrastructure projects like high-level radioactive waste repositories must be sited in areas of extremely low disruption probability by igneous activity. In Germany, according to the Repository Site Selection Act of 2017...
Authors
A. Bartels, L.H. Rummel, F. Mayle

A comparison of non-contact methods for measuring turbidity in the Colorado River A comparison of non-contact methods for measuring turbidity in the Colorado River

Monitoring suspended-sediment concentration (SSC) is essential to better understand how sediment transport could adversely affect water availability for human communities and ecosystems. Aquatic remote sensing methods are increasingly utilized to estimate SSC and turbidity in rivers; however, an evaluation of their quantitative performance is limited. This study evaluates the performance...
Authors
Natalie K. Day, Tyler V. King, Adam R. Mosbrucker

Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau

A detailed characterization of the >3,000 square kilometer (km2) Springerville volcanic field, located on the southern tip of the Colorado Plateau in Arizona, United States, with its more than 501 volcanic units and widely distributed >420 cinder cones and lava flows, provides constraints toward an integrated petrogenetic model for the field. Large-volume effusive tholeiitic eruptions at...
Authors
Marissa E. Mnich, Christopher D. Condit
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Melt Inclusions

Transmitted light photographs of melt inclusions trapped in quartz phenocrysts from the Sciuvechi lava at Pantelleria, Italy. Reprinted from Lowenstern (1994: American Mineralogist 79:353-369). (A) Inclusion P32-39 (60µm in maximum diameter) was experimentally heated to ~825°C and then cooled to 700°C, at which time three small vapor bubbles nucleated. All bubbles nucleated either on the quartz wall or a refractory quartz bleb (q). None nucleated on a small droplet of hydrosaline melt (h), which is ~60-70wt.% molten NaCl, and was trapped along with the melt during crystallization of the quartz. (B) Two hydrosaline melt droplets (4 µm diameter each) were present within P32-49.1 (105 µm in maximum diamter). During heating at 875°C, some opaque crystals (o) remained unmelted but were dissolved above 900°C. (C) During cooling, below 490± 15°C, the hydrosaline melts crystallized and could not be clearly viewed except at 1250X magnification (D and E, for left and right hydrosaline melts, respectively), which showed them to consist of host glass (m), a vapor (+ liquid?) bubble, and a white crystal with cubic habit (presumably halite). The host crystal was flipped and rotated before photographing D and E.

Volcano Hazards Program | U.S. Geological Survey Skip to main content
U.S. flag

An official website of the United States government

Volcano Hazards Program

Find U.S. Volcano

There are about 170 potentially active volcanoes in the U.S. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption through our National Volcano Early Warning System. We deliver forecasts, warnings, and information about volcano hazards based on a scientific understanding of volcanic behavior.

News

Volcano Watch — Mauna Loa has lessons to teach during quiet times

Volcano Watch — Mauna Loa has lessons to teach during quiet times

Photo & Video Chronology — February 16, 2026 — Kīlauea episode 42 fountains and fallout

Photo & Video Chronology — February 16, 2026 — Kīlauea episode 42 fountains and fallout

Volcano Watch — New Hawaii citizen science tool: Is Tephra Falling?

Volcano Watch — New Hawaii citizen science tool: Is Tephra Falling?

Publications

Forecasting volcanic activity in Germany—A multi-criteria approach Forecasting volcanic activity in Germany—A multi-criteria approach

Igneous activity, including shallow intrusions and volcanism, has the potential to disrupt underground critical infrastructure. Notably, future underground infrastructure projects like high-level radioactive waste repositories must be sited in areas of extremely low disruption probability by igneous activity. In Germany, according to the Repository Site Selection Act of 2017...
Authors
A. Bartels, L.H. Rummel, F. Mayle

A comparison of non-contact methods for measuring turbidity in the Colorado River A comparison of non-contact methods for measuring turbidity in the Colorado River

Monitoring suspended-sediment concentration (SSC) is essential to better understand how sediment transport could adversely affect water availability for human communities and ecosystems. Aquatic remote sensing methods are increasingly utilized to estimate SSC and turbidity in rivers; however, an evaluation of their quantitative performance is limited. This study evaluates the performance...
Authors
Natalie K. Day, Tyler V. King, Adam R. Mosbrucker

Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau Toward a four-dimensional petrogenetic model of a distributed volcanic field on the southern edge of the Colorado Plateau

A detailed characterization of the >3,000 square kilometer (km2) Springerville volcanic field, located on the southern tip of the Colorado Plateau in Arizona, United States, with its more than 501 volcanic units and widely distributed >420 cinder cones and lava flows, provides constraints toward an integrated petrogenetic model for the field. Large-volume effusive tholeiitic eruptions at...
Authors
Marissa E. Mnich, Christopher D. Condit
Was this page helpful?